In pot fusing, Method (1) above, it is known to use as ingredients in the heat transfer fluid, surfactants and/or polyglygols with or without antioxidants. Antioxidants are used to extend the pot life of the heat transfer fluid, which may run as long as a week. The surfactants create foaming and cleaning difficulties of the sort described above in connection with radiation fusing fluids.
Pot fusing is the process most nearly related to radiation fusing; but this invention relates to the latter.